Both were operated by well-known airlines with strong safety records
-- but the Lion Air flight went down 13 minutes after take off, while Sunday’s Ethiopian Airlines flight crashed just six minutes into its
journey.

I know "after doing something". So I guess "take off" here is a noun phrase.

@Zhang MW are out of step. The Oxford and Cambridge dictionary hyphenate it. See here: link and here link. It matters not; the important thing is that it is a compound noun, not a noun phrase.
– BillJMar 11 '19 at 11:47

Both were operated by well-known airlines with strong safety records -- but the Lion Air flight went down 13 minutes after take off, while Sunday’s Ethiopian Airlines flight crashed just six minutes into its journey.